Introduction

This section was originally intended to start discussing the content of 802.11e, because the birth and formation of wireless local area networks, especially during the evolution process, an important starting point is 802.11e. Many of the contents introduced in 802.11n, 802.11ac, and 802.11ah can actually be found in 802.11e, and more generally, the earlier 802.11 MAC layer protocols are basically designed according to the EDCF in 802.11e rather than the traditional DCF.

However, if we directly discuss the evolution of the 802.11 protocol starting from 802.11e, it might be a bit conflicting, because the evolution process has been ongoing since the protocol’s inception, or even before the protocol began. Therefore, this article aims to summarize the general evolution of the WLAN protocol based on the author’s personal understanding.

Some of the contents in this article reference the following citations:

1. “The Innovation Journey of Wi-Fi (The Road to Global Success)”

2. “THE HISTORY OF WI-FI”

3. “Ethernet: The Definitive Guide”

The rest are some summaries from the author; if there are any inaccuracies, please forgive me.

The Origin of Wi-Fi Protocol

Wi-Fi is a WLAN (Wireless LAN) protocol. Its history, or the history of multiple access protocols in network protocols, can be traced back to ALOHAnet in 1971.

PS: Before ALOHAnet, there was also a local area network architecture called University of California Irvine Ring, which will not be elaborated on in this article.

According to Wikipedia, ALOHAnet was constructed by a team led by Norman Manuel Abramson at the University of Hawaii. Because it was difficult to lay wired connections between islands, and if laid, the cost would be high, Norman hoped to use relatively inexpensive wireless devices to build a wireless link for communication between Oahu and other Hawaiian islands. The project was initiated in September 1968, and by June 1971, the first data packet was successfully sent at a rate of 9600bps. The communication protocol designed for this network is now known as the Aloha protocol (more accurately, pure-Aloha).

• The idea of the Aloha protocol is as follows: “An aloha node can send immediately whenever it has data. After the node has finished sending its data, it needs to wait for an ACK from the receiver. If the ACK is successfully received, the transmission is successful. If no ACK is received, the transmission fails. The aloha node assumes that there is another aloha node in the network also sending data, causing a collision at the receiver. Finally, these colliding nodes will randomly choose a time to back off to avoid the next collision. Once the backoff is complete, the nodes can attempt to resend.”

The Aloha protocol was the first to discuss a network protocol for transmission over a shared medium, which is the prototype of the earliest local area networks and can also be referred to as multiple access mode. CSMA/CD in wired networks and CSMA/CA in wireless networks, among others, are optimized based on this idea. Norman Abramson led the proposal of this protocol and subsequently conducted theoretical analysis and improvements on it, for which he received the “IEEE’s Alexander Graham Bell Medal” in 2007.

Two years after the birth of ALOHAnet, on May 22, 1973, Robert “Bob” Metcalfe at Xerox’s Palo Alto Research Center in California built a new network system that connected a group of computers known as Xerox Alto, creating a high-speed LAN. Initially, Metcalfe named the network “Alto Aloha Network,” indicating that this network was also derived from ALOHAnet, but later he renamed it “Ethernet.” “Ether” refers to the medium through which electromagnetic waves propagate, and according to [3], Metcalfe intended to indicate its essence by naming it Ethernet, meaning this is a network that transmits through a physical medium.

Ethernet designed a relatively complete local area network architecture, including specific physical interfaces, transmission medium designs (as shown above), and corresponding network protocols (i.e., CSMA/CD). CSMA/CD (Carrier Sense Multiple Access with Collision Detection) introduced the LBT (Listen Before Talk) mechanism on top of the Aloha protocol. The CS in the protocol name (Carrier Sense) is a specific implementation of LBT, which means “listen first through CS, and only transmit when the channel is free.”

• The idea of the CSMA/CD protocol is as follows: “A node must continuously listen to the channel before sending data. Once the node finds the channel free, it immediately sends data. While sending data, the node continues to listen to the channel to detect if other nodes are also sending data at that moment.

• If no other nodes’ transmissions are detected during the transmission process, the transmission is successful. After successful transmission, the node must wait for the inter-frame gap (IFG) time before it can perform the next transmission.

If a collision is detected during the transmission process, the node immediately stops the current transmission and sends a specific JAM sequence to strengthen the collision (to ensure that all other nodes detect this collision). After the JAM sequence is sent, the node randomly selects a time to back off. Once the backoff is complete, the node can attempt to retransmit.”

• PS: More detailed content about the early design of Ethernet can refer to [3] or “Ethernet: Distributed Packet Switching for Local Computer Networks”.

In 1980, Metcalfe initiated the standardization of Ethernet, resulting in the release of the DIX protocol. The name DIX includes the names of American companies DEC, Intel, and Xerox. Under Metcalfe’s leadership, DIX embraced openness from the start. Anyone could copy and use the DIX protocol, and because of this, Ethernet quickly became the world’s first open, multi-vendor LAN standard. Metcalfe was also the founder of 3COM.

PS: The DIX protocol is currently difficult to find in electronic format. The resources I found are as follows: “DIX Network Protocol (including V1 and V2)”.

At the same time, another organization, IEEE, was also standardizing Ethernet. According to [3] and “Overview and Guide to the IEEE 802 LMSC,” this standardization also established a new organization, the IEEE 802 Committee.

The standard system issued by the IEEE 802 Committee is relatively complete, setting up multiple different groups to specify corresponding protocols in different scenarios. Ethernet corresponds to 802.3, and Token Ring is 802.5. These protocols were successively issued between 1985 and 1986.

The topic we are going to discuss now is the Wi-Fi protocol of wireless local area networks, which is the specific protocol designated by the eleventh group of this committee (i.e., IEEE 802.11). Under each group, there are also different task groups (such as 802.11a/b/g/n/ac/ax, etc.).

Here, we summarize the first timeline, referring to [1].

From the above figure, we can also see that with the development of time, the income of the network industry and the number of corresponding products have been steadily increasing. The above is a discussion of the origin of wireless local area network protocols, and next we will formally discuss the birth of the Wi-Fi protocol.

PS: In the development of networks, wireless communication is not limited to the development of wireless local area networks; the main focus is still on communication networks. However, since this article only discusses wireless local area networks, the author has limited knowledge of the development of communication networks, so it will not be elaborated on.

The Birth of the Wi-Fi Protocol

The development of civilian networks often has to go through the approval of policies. In the United States, the birthplace of network development, the policy refers to the licenses issued by the US Federal Communications Commission (FCC) for the use of radio frequency bands. To avoid interference with radar, in 1985, the FCC issued ISM licenses for industrial, scientific, and medical sectors, opening up the 900MHz, 2.4GHz, and 5.8GHz frequency bands, allowing nodes to use only spread-spectrum technology for communication at that time.

Before the ISM frequency band, wireless communication, such as radio and television broadcasting, used dedicated frequency bands to avoid harmful radio interference. The ISM frequency bands were chosen because they are not critical to primary businesses and are also susceptible to radio interference; for example, microwaves also operate in the 2.4GHz band, so the ISM frequency range is regarded by the industry as “garbage bands.”

However, regardless, the FCC’s opening of the ISM frequency band allowed the development of wireless local area networks. It is also because of some problems with ISM that certain design mechanisms in wireless local area network protocols were affected. However, if we expand on why the FCC opened the ISM frequency band at that time and limited it to spread-spectrum transmission, it is also the result of industry lobbying, which can also be traced back to a feasibility report by MITRE in 1980, which corresponds to the FCC’s results.

PS: Hedy Lamarr is often referred to as the mother of Wi-Fi because the FCC only allowed spread-spectrum communication in the ISM band, making the prototype design of Wi-Fi based on spread-spectrum. Hedy Lamarr is more generally known as the creator of spread-spectrum technology (actually frequency-hopping technology, inspired by the piano or automatic piano), so in this sense, it can also be considered reasonable.

After the ISM frequency band was opened, the first product of wireless local area networks, WaveLAN, quickly emerged. WaveLAN was designed by Vic Hayes in 1987-1988 as the first wireless LAN product. While working for NCR Corporation, Vic Hayes aimed to build a wireless cash register system and constructed the initial wireless local area network, WaveLAN, by referencing the ideas of previous Ethernet and Token Ring networks. This design was an Ad-Hoc network and is often considered the prototype of Wi-Fi design, marking the beginning of the gradual development of Wi-Fi.

In 1989, NCR took the lead in planning to construct a dedicated protocol for wireless local area networks under the IEEE 802 organization. According to [1], in fact, the design of WaveLAN began in 1987, and the initial idea was to modify only the layers related to wireless access media, namely the PHY and MAC layers, based on the OSI seven-layer architecture.

• The initial design of the MAC layer had two voices: one representing centralized control (Merits of Central) by IBM, and the other representing distributed control (Distributed Control Architecture) by NCR (including NCR/Symbol Technologies/Xircom). Ultimately, the distributed control approach represented by NCR won the initial victory. From the author’s perspective, this also marked the beginning of the coexistence of distributed (DCF, EDCA) and centralized (PCF, HCCA) design in the Wi-Fi protocol.

• The initial design of the PHY included two possible spread-spectrum methods: frequency hopping and direct-sequence spread spectrum. This was also due to the FCC’s initial issuance of the ISM license, which only allowed spread-spectrum communication. At the beginning of the protocol design, the team could not decide on only one of the two methods, so both physical-layer spread-spectrum schemes were supported in the final published protocol.

In 1990, the IEEE 802.11 committee was officially established. As the designer of WaveLAN and the main promoter of the 802.11 protocol, Vic Hayes is also known as the “Father of Wi-Fi.”

In the same year, NCR also officially released the first WaveLAN product, as shown in the figure above. This is the first network card that provided WaveLAN functionality for desktop computers, operating in the 915MHz band and capable of providing a transmission rate of 2Mbps.

The initial WaveLAN was designed for an Ad-hoc self-organizing network structure, primarily to establish a wireless communication link. The concept of wireless routers, which are widely present in our homes today, emerged after the birth of WaveLAN. Although [1] does not mention it, according to WiKi, the concept of hotspot access was proposed in 1993 by Henrik Sjödin. The concept mentioned in [1] can be traced back to 1993, but at the same time, many others also proposed similar concepts.

Moreover, according to [1], the originally proposed concept of hotspot should be more directly referred to as WISP, i.e., Wireless ISP. ISP (Internet Service Provider) refers to network operators, so the initial idea was to construct a small base station (corresponding to the hotspot) within the ISM licensing range using a wireless network protocol like WaveLAN, which could directly connect to the ISP network. This is more directly the prototype of the current wireless local area network infrastructure, where the hotspot has some differences from the current discussions, as the current hotspot emphasizes providing network service in public areas, while the initial hotspot concept refers to the infrastructure model of our current wireless local area networks, which includes a wireless AP (simply understood as a home wireless router) connecting to the public network.

The concept of hotspots is also one of the key factors for the success of the Wi-Fi protocol, as it is one of the most important components of Wi-Fi’s commercial application. The demand for hotspots has greatly promoted the development of the Wi-Fi protocol, including roaming, security, and multi-AP extended ESS modes.

In the same year, AT&T deployed the first large-scale WaveLAN network at Carnegie Mellon University, marking the first important attempt at large-scale deployment of wireless local area networks.

Following the successful deployment of a large WaveLAN network, in 1994, Dr. Alex Hill led the launch of a wireless infrastructure project called “Wireless Andrew” at Carnegie Mellon University. This project aimed to allow students to connect mobile devices to the network through WaveLAN in a campus environment, enabling students to learn anywhere, which was also referred to as the concept of “mobile learning.” The project was very successful and demonstrated the advantages of wireless network access.

What we have discussed so far is WaveLAN, while we currently refer to wireless networks as Wi-Fi. If explained in Chinese, Wi-Fi means wireless high-fidelity networks. How to achieve high fidelity in wireless networks effectively, enabling data transmission to meet our current Wi-Fi usage demands, is generally believed to have been accomplished in 1996 by a group led by John O’Sullivan from CSIRO in Australia (mainly based on the patent filed in 1996, US Patent Number 5,487,069). Some people also refer to “John O’Sullivan” as the father of Wi-Fi because this concept originated from him. Wi-Fi was initially a complete independent protocol, the main content of which was later accepted by IEEE 802.11, thus becoming the standard for 802.11a. In fact, IEEE also had disputes with the Australian government regarding the patent issue of the Wi-Fi protocol, which involves patent fees.

In 1997, after two rounds of voting, the first version of the 802.11 protocol was officially approved in September and published on December 10, 1997 (i.e., IEEE 802.11-1997). The first version of the protocol included both frequency hopping and direct-sequence spread spectrum modes, with frequency hopping supporting a mandatory rate of 1Mbps and an optional rate of 2Mbps, while direct-sequence spread spectrum required both 1Mbps and 2Mbps to be supported.

At the same time, in addition to the IEEE 802.11 protocol, many WLAN protocols were also being developed simultaneously. Some originated from telephone networks, such as HomeRF, while others originated from ATM networks, such as HIPERLAN, with the basic purpose of building a wireless communication network in the ISM frequency band.

Although many people now equate WLAN, Wi-Fi, and IEEE 802.11 as the same concept, there are actually distinctions among these terms. WLAN is a broader concept that includes Wi-Fi, or the IEEE 802.11 protocol, as well as HomeRF and HIPERLAN protocols. Other protocols have become part of history for various reasons, and currently, we can basically equate WLAN protocols with Wi-Fi protocols.

From the above figure, we can summarize the origin and birth of Wi-Fi, and we can clearly see that the emergence of Wi-Fi was the result of a long period of accumulation, continuously expanding its functionalities. Starting in 2001, once there was a business demand, it transformed from a technological accumulation into an engineering industry. Next, we will formally discuss the rapid development process of the Wi-Fi protocol.

We also summarize the three important figures related to the origin of Wi-Fi mentioned earlier:

• Hedy Lamarr: Many media refer to her as the “mother of Wi-Fi” because she created the initial “frequency-hopping communication” transmission method through piano practice. Frequency hopping is a basic method of spread spectrum communication. When the FCC opened the ISM frequency band in 1985 and required the academic community to design wireless communication protocols, it stipulated that spread-spectrum communication methods must be used. Therefore, Hedy Lamarr, known as the “mother of frequency hopping,” has also been referred to as the “mother of Wi-Fi.”

• Vic Hayes: Hayes is widely recognized in both academia and industry as the “father of Wi-Fi.” He created the first generation of the WaveLAN practical platform and actively promoted and led the establishment of the IEEE 802.11 committee and the initial construction of the 802.11 and 802.11a/b/g protocols, making significant contributions to the overall development of Wi-Fi.

• John O’Sullivan: John is often referred to as the “father of Wi-Fi” by Australian media, which is also reasonable. Compared to Hayes, who focused more on wireless local area network communication, John was mainly concerned with proposing the concept of “Wi-Fi,” which is high fidelity, and also realized a complete design based on the “Wi-Fi” concept. From this perspective, he can also be called the “father of Wi-Fi.”

The above is a summary of some figures related to the origin of Wi-Fi based on the materials I have read so far. If there are any inaccuracies, please forgive me.

The Development of the Wi-Fi Protocol

Due to the formal issuance of the IEEE 802.11 protocol and the gradual maturation of early wireless network technology, in 1998, a company called MobileSTAR began officially providing commercial-grade wireless local area network services. Initially, its services focused on airports, hotels, and coffee shops. In 2001, Starbucks chose MobileSTAR as its wireless network service provider, and with the successful operation of the Wi-Fi hotspot business model, the research and development of Wi-Fi technology entered a rapid growth phase.

In 1999, the Wi-Fi Alliance was officially established. At that time, it was not yet called the Wi-Fi Alliance; it was initially referred to as WECA (Wireless Ethernet Compatibility Alliance). This was a non-profit organization initiated by the industry. While the IEEE protocol focused on theoretical design, a key issue that needed to be resolved in real production environments was the interoperability of different manufacturers’ products and product testing. The WECA alliance was established for this purpose, initially focusing on the Direct Sequence Spread Spectrum (DSSS) technology in IEEE 802.11. In 2002, WECA officially changed its name to the Wi-Fi Alliance.

In the same year, IEEE issued the 802.11b protocol. The 802.11b protocol added the HR/DSSS (High-Rate Direct Sequence) mode at the physical layer compared to the initial IEEE 1997 issuance, introducing CCK encoding, thus providing two new rates of 5.5Mbps and 11Mbps, along with the 1Mbps and 2Mbps rates specified by IEEE 2007 (based on Barker code), totaling four selectable rates.

Let’s briefly explain the Direct Sequence Spread Spectrum (DSSS) mode. In direct-sequence spread spectrum, there is a concept called spread spectrum sequence (as shown in the second row of the above figure, Barker Sequence).

• If the network does not use spread spectrum, when we want to send a digital signal “1,” we need to send a Bit Sequence maintaining a fixed signal amplitude.

• If the network uses spread spectrum technology, when we want to send a digital signal “1,” we send not a fixed signal amplitude but a corresponding spread spectrum sequence during that time interval.

The Barker and CCK encoding mechanisms used in 802.11, along with the corresponding matching decoding mechanisms, can resist noise and multipath effects with relatively low complexity. The transmission mode designed in 802.11b is still the method with the farthest transmission coverage in Wi-Fi today.

PS: We will discuss the spread spectrum technology used in 802.11b in detail in other topics later.

In 1999, there was intense competition between HomeRF technology and 802.11b technology. HomeRF used frequency hopping technology, while 802.11b focused on direct-sequence spread spectrum technology. Although the initial IEEE 802.11 1997 specified both frequency hopping and direct-sequence spread spectrum modes, later 802.11 and most companies engaged in wireless technology focused more on implementing the simpler and more direct DSSS method. This is why 802.11 gained an advantage in the competition with HomeRF.

In fact, many people began to encounter Wi-Fi starting from 802.11b, which was the first milestone in the 802.11 protocol. Early laptops or PSP game consoles with Wi-Fi functionality were based on 802.11b. The 802.11b protocol was a significant step in the development of wireless networks.

In the same year, Apple officially launched Airport technology based on Wi-Fi principles in iBooks.

One year later, another version of 802.11, 802.11a, was officially approved. However, 802.11a can be considered a version that was not well-timed, as it did not achieve the same success as 802.11b in its era.

802.11a introduced a new physical layer technology called OFDM (Orthogonal Frequency Division Multiplexing). OFDM technology was proposed in the 1960s, but its core algorithm, FFT, was complex. With the development of integrated circuit technology, OFDM technology began to be adopted in communication engineering in the 1990s. Compared to spread spectrum technology, OFDM technology has higher spectral efficiency. As shown in the figure above, OFDM maps multiple digital signals onto multiple frequency domain subcarriers and then synthesizes these digital signals for simultaneous transmission through IFFT. Through OFDM, higher spectral efficiency can be achieved, increasing transmission rates. We will elaborate on the details of OFDM in future discussions, so we will not go into detail here.

802.11a did not perform well mainly due to frequency band issues. At that time, the FCC had only opened a few designated channels for non-military use of the 5GHz band. Moreover, since 802.11a and 802.11b operated in different frequency bands, requiring new devices to be compatible with both 802.11b and 802.11a would increase costs, resulting in limited practical application of 802.11a.

802.11g and 802.11a protocols are generally consistent. More generally, 802.11g is a migration of 802.11a to the 2.4GHz band, with some compatibility designs added.

Initially, the FCC did not allow the use of OFDM technology in the 2.4GHz band, only permitting spread spectrum technology. In 2002, the FCC changed the rules to allow OFDM technology in the 2.4GHz band, leading to the formal approval of the 802.11g protocol in 2003.

The physical layer of the 802.11g protocol is called the Enhanced Rate Physical Layer (Extended Rate PHY, ERP), which provides five operating modes for compatibility with the previous 802.11b protocol: ERP-DSSS, ERP-CCK, ERP-OFDM, DSSS-OFDM, and ERP-PBCC. The 802.11g protocol is the second milestone in the 802.11 protocol, and we will summarize the detailed content of this protocol in future articles.

Due to the limited available channels in the 802.11a protocol, at the 2003 World Radiocommunication Conference, European radio regulatory authorities proposed to increase the available frequency band by 455MHz in the 5GHz band for HIPERLAN-related protocols. This provided significant resources for the further development of Wi-Fi protocols in the 5GHz band, as this newly added 455MHz ISM band would later become an important channel resource used by 802.11ac protocols.

In the same year, CALYPSO released a phone that could communicate via Wi-Fi, providing more possibilities for the commercial application of Wi-Fi.

In 2004, due to the traditional Wi-Fi development focusing on the performance of its PHY and MAC layers, the security of the protocol had not been well guaranteed. Therefore, in 2004, a dedicated security standard for Wi-Fi, 802.11i, was officially issued. In fact, during this period, there was also a protocol initiated in China called WAPI, which also aimed to address this issue.

In 2005, an important improvement to the 802.11 MAC, the 802.11e protocol, was officially approved. The 802.11e protocol provided many specific methods for improving the performance of traditional 802.11 networks, such as introducing EDCA/HCCA for MAC access mechanisms, TXOP, Block ACK, etc. The MAC protocols we currently use and the main versions of the protocols (such as IEEE 802.11 2007/2012/2016) are all directly based on the forms specified in 802.11e. We will discuss the content of 802.11e in detail later.

By 2005, 100 million Wi-Fi chips had been produced, and the development of wireless local area networks had begun to take shape, officially entering a period of prosperity. At the same time, communication networks began to develop towards 3G networks.

The Prosperity of the Wi-Fi Protocol

In 2009, the third milestone of Wi-Fi development, the 802.11n protocol, was officially approved. Generally speaking, product development often occurs after the standardization work, with many products being released after the standard is announced. In fact, starting from the 802.11n protocol, manufacturers began releasing products with the 802.11n title based on the draft that was ultimately confirmed, competing to capture the market, many of which did not achieve good compatibility with the final standard. In 2007, the 802.11n draft evolved into version 2.0, and by 2009, its version 3.0 was officially approved as the protocol.

During the discussion of the 802.11n protocol, two main proposal factions emerged: TGn Sync (mainly including Intel, Cisco, Agere, and Sony) and WWiSE (mainly including Broadcom, Conexant, and Texas Instruments). During the voting process, TGn Sync initially held an advantage, but the protocol ultimately did not pass. Only when Intel and Broadcom from both factions combined their respective viewpoints to form a new faction, the Enhanced Wireless Consortium (EWC), did they break the previous deadlock. After multiple revisions of the draft, the protocol was finally approved in March 2009.

Compared to previous Wi-Fi technologies, the core technical concept of 802.11n is MIMO. In previous wireless communications, we used single-antenna transmission systems. In the design of MIMO, we can transmit multiple different data in parallel using multiple antennas (as shown above, simultaneously transmitting x1 and x2 signals to the RX end), thus improving transmission rates and providing higher system bandwidth.

By 2009, the scale of Wi-Fi chips had expanded to one billion.

In the same year, while the Wi-Fi protocol was rapidly developing, another committee, IEEE 802.16, also launched a new W-WAN protocol, WiMAX. WiMAX differs from Wi-Fi in that it focuses on providing wireless network access over longer distances.

In fact, in the development of networks, various technologies from different sources often interact (as shown in the figure above). However, whether they succeed or not depends on market and timing. For example, Wi-Fi has achieved significant success, while WiMAX has not been widely adopted.

In 2009, another noteworthy event was the patent dispute regarding Wi-Fi technology involving CSIRO, which ultimately ended with CSIRO obtaining $200 million in compensation.

By 2010, the number of Wi-Fi hotspots had reached one million.

In 2010, with the support of then-President Obama, the FCC agreed to add 500MHz of new frequency bands for wireless communication in the future. This 500MHz is spread across multiple different frequency bands, specifically set according to functional needs.

In 2012, CSIRO’s technology patents led to a second patent dispute regarding Wi-Fi technology.

After the 802.11ac period, the public had become much more familiar with Wi-Fi technology, and there was an increasing demand for and engagement in wireless business. In 2014, the fourth milestone of Wi-Fi, the 802.11ac technology, was officially approved, with the key term being MU-MIMO.

As shown in the figure above, in traditional single-beam networks, only one device can send data at the same time (as shown in the left blue area, only one person can send at a time). Under MU-MIMO technology, by refining the beams, as shown in the right blue area, the router sends two beams, targeting both a laptop and a phone, achieving simultaneous transmission. In 802.11ac, only downlink MU-MIMO is supported, while uplink is not. We will not elaborate on other technical details of 802.11ac here.

In 2014, the first 802.11ac router was released. During the specification process of the 802.11ac protocol, there was also a phenomenon of products being released ahead of the protocol, resulting in distinctions between wave 1 and wave 2 in current 802.11ac products.

By 2015, the number of Wi-Fi hotspots had reached seventy million.

The Future of the Wi-Fi Protocol

Currently, Wi-Fi has developed into a new type of wireless ecosystem, and its functions are no longer limited to the transmission of standard Internet data. Depending on different working scenarios and needs, there are different protocol versions.

As a mature technology that has developed for 46 years, Wi-Fi continues to evolve, and we cannot simply analyze a specific scenario to determine its development trends and value. The future of the Wi-Fi protocol looks promising. The discussions above primarily trace the history of the development of Wi-Fi to date, hoping to provide some reference for everyone.

SourceWi-Fi_Researcher

END

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